Effects of NPK source on the dry matter partitioning in cool season C3-cereals (wheat,rye, barley,and oats) at various growth stages

Dry matter (DM) partitioning into root, leaf, stem, shoot dry weight plant^?1 response in four cool season C₃-cereals viz. wheat (Triticum aestivum L.), rye (Secale cereale L.), barley (Hordeum vulgare L.) and oats (Avena sativa L.) was investigated at 30, 60 and 90 days after emergence (DAE) under eight nitrogen, phosphorus and potassium (NPK) sources: S₁ = 20-20-20, S₂ = 20-27-5, S₃ = 7-22-8, S₄ = 10-10-10-20S, S₅ = 11-15-11, S₆ = 31-11-11, S₇ = 24-8-16, and S₈ = 19-6-12 in pot experiment at Dryland Agriculture Institute, West Texas A&;M University, Canyon, Texas, USA during winter 2009-10. A considerable variation in DM partitioning into various plant parts was observed in the four crop species at different growth stages and NPK source. At 30 DAE, 27% of the total DM per plant (TDMPP) was partitioned into roots and 73% into shoots (19% stems + 54% leaf). Only16 % of the TDMPP was partitioned into roots and 84% into shoots (18 % stem + 66 % leaf) at 60 DAE. At 90 DAE, 29% of TDMPP was partitioned into roots and 71 % into shoots (33 % stems + 38 % leaf) at 90 DAE. Percent DM partitioning into stems ranked first (33%) at 90 DAE > at 30 DAE (19%) > at 60 DAE (18 %). With advancement in crops age, DM partitioning into various crop parts increased. The root DM plant^?1 (RDMPP) increased from 11.5–722 mg plant^?1; stem DM plant^?1 (STDMPP) from 8.3–889.0 mg plant^?1; leaf DM plant^?1 (LDMPP) from 23.1–1031.0 mg plant^?1; shoot DM plant^?1 (SHDMPP) from 31.3–1921 mg plant^?1, and TDMPP increased from 42.9–2693.0 mg plant^?1 at 30 and 90 DAE, respectively. Because of the higher N contents in S₇ (24:8:16) and S₆ (31:11:11) reduced the DM partitioning into various plants parts as well as TDMPP at all three growth stages. The adverse effects of S₆ and S₇ on DM partitioning was more on oats > rye > wheat > barley. The S₄ with 10:10:10 (NPK) and :20S was not toxic at 30 DAE, but at 60 and 90 DAE it became toxic that adversely affected the DM partitioning as well as TDMPP probably may be due its high sulfur (20%) content which lacking in other NPK sources. The DM partitioning to various parts of barley and wheat was more than oats and rye at different growth stages (barley > wheat > rye > oats). Since the DM portioning values were determined on the average of five plants in pot experiment under organic soil at field capacity; in case of field experiments more research is needed on various crop species/varieties under different environmental conditions particularly under moisture stress condition.     

Two years of a field study on sesame growth and yield,nutrient uptake by PGP bacteria application and capsule type

Abstract

A two-year field experiment was conducted to study PGP bacteria on growth and yield productivity of sesame. Factors were control, Nitroxin, Biophosphor, and an equal combination of biofertilizers along with sesame capsule type. 1000-seed weight and oil content increased in the second year, but, seed yield reduced (-12.6?g m²), which represented a negative relationship between seed weight and yield. The effect of year on No. of single and multi-cap node plant^?1 was reversed. Seed yield, chlorophyll, protein, and N increased in the multi-cap seed, whereas, 1000-seed weight and seed weight plant^?1 was decreased. Maximum yield and yield components were achieved in the second and first year, respectively, along with the multi-cap seed. Nitroxin, after the equal combination, was approximately showed the maximum enhancement of growth and yield productivity of sesame. The most seed yield (4261 k ha^?1) was performed in the first year, combined biofertilizers and multi-cap seed, whereas, the highest oil content was gained in the second year and single-cap that it was due to the higher N and P use efficiency in the first year. No. of node plant^?1 and capsule No. plant^?1 showed the most correlation with the other parameters. Seed yield was correlated with No. of node plant^?1 (r?=?0.925) and leaf dry weight (r?=?0.885). The N and P use efficiency had been higher in the first year, multi-cap, and equal combination. Nitrogen Use efficiency was higher compared to phosphorous. The uptake of N and P by sesame increased with the integrated application of different bacteria.     

Specific Leaf Area and Specific Leaf Weight in Small Grain Crops Wheat,Rye, Barley,and Oats Differ at Various Growth Stages and NPK Source

Leaf thickness plays an important role in leaf and plant functioning and is related to species’ strategies of resource acquisition and use. Leaf thickness in small grains crops was measured as specific leaf area (SLA) (leaf area in cm² produced g^?1 leaf dry weight plant^?1) and specific leaf weight (SLW) (leaf dry weight in mg produced cm^?2 leaf area plant^?1). The four small grains crops (cool season C₃ cereals) studied were wheat (Triticum aestivum L.), rye (Secale cereale L.), barley (Hordeum vulgare L.) and oats (Avena sativa L.). The null hypothesis tested was that SLA and SLW in small grain crops do not differ at different growth stages and nitrogen, phosphorus, and potassium (NPK) source. Eight NPK sources used in the experiment were: S₁ = 20-20-20, S₂ = 20-27-5, S₃ = 7-22-8, S₄ = 10-10-10-20S, S₅ = 11-15-11, S₆ = 31-11-11, S₇ = 24-8-16, and S₈ = 19-6-12, and each was applied at the rate of 300 mg pot^?1 at the time of sowing to each crop species. The experiment was performed in completely randomized design with three repeats at the Green House of Dryland Agriculture Institute, West Texas A&M University, Texas, during winter 2009-10. Based on the results, it was observed that both SLA and SLW differed with change in crop species, growth stage and NPK source. Among the crop species, SLA was greater in oats > barley > rye > wheat at different growth stages; while SLW of wheat and rye > barley and oats. The differences in the SLW between wheat vs. rye; and between oats vs. barley at different growth stages were not significant (P ≤ 0.05). Among the NPK sources, application of S₇ (24: 8: 16) had higher SLA at 60 and 90 DAE (days after emergence). Application of S₆ (31: 11: 11) had higher SLW at 60 DAE due to the production of the lowest leaf area plant^?1, but the increase in SLW at 90 DAE with S₅ and S₄ was due to the higher leaf dry weight plant^?1produced. Leaf dry weight and leaf area plant^?1 were considered the two most important leaf characteristics that influenced SLA and SLW. On the average, SLA increased with passage of time i.e. 0.70 < 520 < 600 cm² g^?1 at 30, 60 and 90 DAE, respectively; but SLW on the other hand, was highest 3.5 at 60 DAE > 2.2 at 90 DAE > 1.5 mg cm^?2 at 30 DAE. The increase in leaf area plant^?1 and decline in the leaf dry weight plant^?1 increased SLA; in contrast, increase in leaf dry weight plant^?1 and reduction in leaf area plant^?1 increased SLW indicated reciprocal relationship between SLA and SLW in the crop species.     

Plant Density and Nitrogen Effects on Maize Phenology and Grain Yield

ABSTRACT

Nitrogen (N) and plant density are considered some of the most important factors affecting crop phenology (days to tasseling, silking, and maturity), morphology (leaves plant^?1, seeds ear^?1, ears 100 plants^?1) and grain yield. The effects of plant density and N on phenology, morphology, and yield of maize (Zea mays L.) at Peshawar in northwestern Pakistan were evaluated during 2002 to 2004. The 2 × 3 × 6 factorial experiment was designed having two plant densities (60,000 and 100,000 plants ha^?1) and three N levels (60, 120, and 180 kg N ha^?1) applied to main plots, while six split application of N in different proportions were applied to subplots in two equal, three equal, three unequal, four equal, five equal and five unequal splits at sowing and with 1st, 2nd, 3rd, and 4th irrigation at two week intervals. All the phenological characteristics were significantly affected by year, plant density, rate and timing of nitrogen application. Year and plant density had no significant effect while rates and split application of N had significant effects on the leaf number plant^?1 and seed number ear^?1. Year, plant density and N rate had significant effects while N splits had no significant effects on the number of ears 100 plants^?1 of maize. Significantly higher grain yield was observed under high plant densities, high N rate and split application of N, while its response to year effects was statistically non-significant. Tasseling, silking and physiological maturity were delayed and maximum grain yield was obtained from those plots maintained at higher plant density. Delaying in the phenological characteristics while increasing the number of leaves and seeds plant^?1, and number of ears 100 plant^?1 through high rate and split application of N results in maximum yield of maize at Peshawar. This study suggested that maize production can be maximized through high plant density and high N split application.     

EFFECT OF NITROGEN APPLICATION ON ACCUMULATION AND TRANSLOCATION OF CARBON AND NITROGEN COMPOUNDS IN TWO MAIZE CULTIVARS WITH DIFFERENT SENESCENT APPEARANCE

Field experiments and plant analyses were carried out to investigate the effect of nitrogen (N) application on accumulation and translocation of carbon (C) and N compounds in two maize (Zea mays L.) cultivars with different senescent appearance. Two maize hybrids included “Danyu 13”, an earlier senescent hybrid, and “Simi 21”, a stay-green hybrid. There were four nitrogen treatments: (1) N1: 0 kg N ha^?1, (2) N2: 250 kg N ha^?1 (1/5 N as basal application and 4/5 N as top-dressing at stalk elongation stage only), (3) N3: 250 kg N ha^?1 (1/5 N as basal, 2/5 N as top-dressing at stalk elongation stage and tasselling stage, respectively), (4) N4: 400 kg N ha^?1 (1/5 N as basal and 4/5 N as top-dressing at stalk elongation stage). For Simi 21, a higher percentage of sugar and starch were found in each treatment in root, stem, leaf and grain, in comparison with that for Danyu 13. The highest percentage of sugar and starch, 80% ethanol-soluble N and soluble protein N in each organ could be achieved in N3 treatment for Simi 21 and in N2 treatment for Danyu 13, respectively, which consequently benefited to translocation of C and N from vegetative parts to grain. Excessive N could not produce the highest percentage of sugar and starch, 80% ethanol-soluble N and soluble protein N, but the highest percentage of residue C and N components in each organ for both hybrids.     

Development of Critical Values for the Leaf Color Chart,SPAD and Fieldscout CM 1000 for Fixed Time Adjustable Nitrogen Management in Aromatic Hybrid Rice (Oryza sativa L.)

The nitrogen (N) requirement of hybrid rice is generally greater than in conventional rice varieties. Recommendations for N monitoring at regular intervals of 7–10 days through leaf greenness are available, but farmers are accustomed to apply fertilizer N at selected growth stages only. An inexpensive leaf color chart (LCC) and nondestructive chlorophyll meters were evaluated for site-specific N management strategy in world’s first aromatic rice hybrid PRH-10 at the Indian Agricultural Research Institute, New Delhi. Two field experiments were conducted on PRH-10 with four levels of N (0, 70, 140, and 210 kg ha^?1) during June–October of 2010 and 2011 to determine the LCC, soil–plant analysis development (SPAD), and Fieldscout CM 1000 (CM 1000) values for achieving economic optimum grain yield at three critical growth stages (tillering, panicle initiation, and flowering). Quadratic regression between N levels and grain yield were used to determine economic optimum grain yield (6427 kg ha^?1 in 2010 and 6399 kg ha^?1 in 2011) corresponding to optimum economical dose of 151 kg N ha^?1 (2010) and 144 kg N ha^?1 (2011). Nitrogen concentration in fully expanded youngest leaf correlated significantly (P < 0.01) and positively with LCC score, SPAD value, CM 1000 value, and total chlorophyll concentration at tillering, panicle initiation, and flowering for both years. The critical LCC score, SPAD, CM 1000 values, chlorophyll concentration, and leaf N concentration obtained were at tillering 4.4, 42.3, 285, and 2.16 mg g^?1 fresh weight and 3.29%; at panicle initiation 4.4, 43.0, 276, and 2.16 mg g^?1 fresh weight and 3.02%; and at flowering 4.5, 41.7, 270, and 2.05 mg g^?1 fresh weight and 2.83%, respectively. Corrective N application should be done when observed leaf N indicator values at a particular growth stage reach or go below the critical values.     

NITROGEN RATES AND ITS TIME OF APPLICATION INFLUENCE DRY MATTER PARTITIONING AND GRAIN YIELD IN MAIZE PLANTED AT LOW AND HIGH DENSITIES

Best nitrogen (N) management practices are most important for increasing maize (Zea mays L.) productivity and profitability in Northwest Pakistan. Field experiments were performed at the New Developmental Research Farm of NWFP Agricultural University, Peshawar during summer 2002 and 2003. Factorial experimental treatments were two plant densities (D₁ = 60,000 and D₂ = 100,000 plants ha^?1) and three N rates (N₁ = 60, N₂ = 120 and N₃ = 180 kg N ha^?1) as main plots, and six split N applications in different proportions at different growth stages of maize (cv. ‘Azam’) in two equal, three equal, three unequal, four equal, five equal and five unequal splits at sowing and with first, second, third, and fourth irrigation at two week intervals as subplots. Application of the higher N rate (180 kg ha^?1) with 4 to 5 splits significantly increased leaf, stem, ear, and total plant dry weight at silking and physiological maturity as well as grain yield plant^?1 at both low and high plant densities. Variation in dry matter partitioning and grain yield in maize due to fluctuation in the rainfall data of the two years suggests zonal specific effective N management practices for sustainable maize production in different agro-ecological zones of Northwest Pakistan.     

Nitrogen Uptake and Remobilization in Maize Hybrids Differing in Leaf Senescence

Abstract

Maize (Zea mays L.) is an important cereal crop with multiple uses in the world. Stay‐green hybrids have been developed because of their higher productivity. Few studies have been conducted to evaluate the influence of nitrogen (N) levels on N uptake, remobilization, grain yield and N concentration in stay‐green hybrids compared to senescent ones. Field studies were undertaken in P.R. China on an Ustochrepts soil to determine the effects of N levels and hybrids differing in leaf senescence on grain yield and N concentration, N uptake, remobilization, and residual in vegetative tissues in 1996 and 1997. The stay‐green hybrid ND108 had greater yields than TK5 (intermediate senescing) and ZD120 (fast senescing) under both high (225 kg N ha^?1) and low N (0 in 1997 or 45 kg N ha^?1 in 1996, respectively) supply. ND108 took up more N than the two other hybrids. Grain N concentration of ND108 did not decrease by low N significantly, excepting the experiment sown in the summer of 1996, when post‐silking N uptake was reduced greatly by the shortened grain filling duration. Nitrogen remobilization efficiency in vegetative tissue was higher in senescent hybrids ZD120 than ND108. Nitrogen retained in the stover at harvest was higher in ND108, which can lead to a deficit of soil N for the next crop if the stover is not returned into soil. It was suggested that, though stay‐green hybrids have been developed for high N conditions, they have advantages over senescent hybrids also under N limited conditions.     

Yield and nitrogen use efficiency of bell pepper grown in SLAB fertigated with different nitrogen rates

Abstract

Adequate plant nutrition is important to reduce costs and increase the crop yield. This study tried to verify the influence of Nitrogen (N) on plant biomass production and the yield of bell pepper grown in SLAB; quantify the N use efficiency (NUE), and to quantify the residual N concentration in the substrate after the end of the crop cycle. The experiment was carried out in a protected environment. Pepper seedlings were transplanted to SLAB bags containing 40?dm³ of substrate. The treatments consisted of six N rates (0, 1.5, 3.0, 4.5, 6.0, and 7.5?g plant^?1) split into 10 fortnightly applications, in a randomized block design with four replications. The fruit yield was evaluated throughout the experiment and after the final harvest, the dry mass of leaves, stem, and root of the plant, the N content and accumulated, the residual nitrate and ammonium in the substrate, and the NUE were evaluated. The rate of 5.51?g plant^?1 of N, corresponding to 355.5?kg ha^?1, provided the maximum yield of commercial fruits of 1.57?kg plant^?1 or 101.2 t ha^?1. With increasing N rate, the residual nitrate concentration in the substrate increased and the NUE decreased.     

Effect of Nitrogen Application Timing on Yield Components,Fodder, Grain,and Oil Yields of Brassica Cultivars

The dual-purpose use of Brassica cultivars means cutting or grazing the crop as fodder and then letting it to re-grow and produce grain with little or no yield penalty. A field experiment was conducted in randomized complete block design with split plot arrangement with three replications. Three Brassica cultivars, three nitrogen application timing, and cutting treatments were included in the experiment. The findings indicated that Brassica cultivar Abasin-95 produced higher fresh and dry fodder yields, seeds pod^?1, seed, biological, and oil yields. However, NIFA Raya resulted in a higher number of pods and branches plant^?1. Likewise, fresh and dry fodder yields were higher with nitrogen (N) application all at sowing. Nitrogen applied in two splits resulted in a higher number of pods plant^?1 and grain yield. Cutting suppressed all parameters except 1000 grain weight. Uncut plots produced significantly higher branches plant^?1, pods plant^?1, seeds pod^?1, seed, biological, and oil yields than cut plots.     

Impact of the use of biofertilizers on cotton ( Gossypium hirsutum ) crop under irrigated agro-ecosystem

High nitrogen fixing, phosphate solubilizing, phytohormones producing isolates of Azotobacter, Azospirillum, Acetobacter and Pseudomonas were used as inoculants for cotton. Important cultures were selected on the basis of their effect on root/shoot length and chemotactic behaviour. Selected bioinoculants were earlier tested for their beneficial properties like nitrogen fixation (ARA), ammonia excretion, IAA production etc. These bio-inoculants were further tested for phosphate solubilization property. Various chosen strains were tested with Desi (HD 123) and American (H 1098) cotton under field conditions (as for wheat). Plant height and boll weight were determined at the time of harvesting whereas survival rate of inoculated bacteria was determined after 30, 80 and 130 days respectively. In the year 2000–01, on the basis of boll number and boll weight plant^?1 AVK 51 (36; 76.2?g plant^?1), HT 57 (27; 56.9?g plant^?1), AC18 (33; 61.5?g plant^?1), Ala 27 (36; 61.4?g plant^?1) and Pseudomonas (34; 71.3?g plant^?1) were identified as significant both for American and desi cotton varieties. Highest survival rate was observed with Mac 68 (33.4 × 10⁵) followed by HT54 (31.5 × 10⁵) after 30 days of sowing, which decreased after 80 days and remained constant up to 130 days. This trend was observed with all the cultures. Similar results were observed in 2001–02. 25?kg ha^?1 N saving was observed with A. chroococcum (AVK51) bioinoculant for cotton crop.     

Wheat Nitrogen Fertilization Under no Till on the Low Altitude Brazilian Cerrado

This study evaluates the effects of different nitrogen (N) rates (0, 50, 100, 150, and 200 kg ha^?1) and sources (ammonium sulfate, urea, and ammonium sulfonitrate with a nitrification inhibitor, Entec®) applied either as a single application during sowing (next to the planting rows) or as side dressing (stage 3.2 on Zadok scale), on production components and grain yield of irrigated wheat grown under no-till in a low-elevation Brazilian cerrado and Dark Red Dystrophic Latosol with clayey-texture. It was adopted a randomized block design (5 × 3 × 2) in factorial scheme with four replications. The N sources provided similar grain yields and chlorophyll contents. Increased nitrogen rates increased grain yield up to the 120 kg N ha^?1, regardless of application time and N source. Nitrogen fertilization as side dressing can be recommended based on leaf chlorophyll readings. Early application of all nitrogen fertilizers at sowing time was viable.     

Integrated Nutrient Management Affects Fruit Yield of Sapota (Achras zapota L.) and Nutrient Availability in a Vertisol

ABSTRACT

We studied the effect of integrated nutrient management (INM) combinations on supplement of plant nutrient for quantitative and qualitative fruit production in sapota. Thus, 17 combinations of INM practices were evaluated on fruit yield of sapota and nutrient availability in a Vertisol of Chambal region, India. The results demonstrated that almost all treatment combinations comprised of recommended dose of fertilizer (RDF), i.e. 1,000:500:500 g NPK plant^?1 with application of organic and inorganic sources of nutrients had a significant effect on the fruit yield of sapota, soil microbial biomass, NPK content of leaf, fruit and soil over control (T₁). Among different treatments, application of 2/3rd part of RDF + 50 kg FYM + 250 g Azospirillum + 250 g Azotobacter plant^?1 (T₁₁) significantly enhanced the number of fruits plant^?1 (327.88), yield plant^?1 (29.03 kg) and yield ha^?1 (4.52 t). However, the soil microbial count of fungi (8.89 cfu g^?1 soil), bacteria (11.19 cfu g^?1 soil) and actinomycetes (5.60 cfu g^?1 soil) at fruit harvest was higher under the 2/3 of RDF +10 kg vermicompost + 250 g Azospirillum + 250 g Azotobacter plant^?1 (T₁₅). The leaf nitrogen content (N, 2.03%) was higher in T_15, while phosphorus (P, 0.28%) and potassium (K, 1.80%) content were higher in T₁₁. It is evident that treatment T₁₁ increased fruit yield by 32% in Sapota cv. Kalipatti compared to control. Therefore, combined application of nutrient sources proved not only beneficial for enhancing fruit yield of sapota but also sustaining soil health in Chambal region of south-eastern Rajasthan.     

Impact of Various Ratios of Nitrogen and Sulfur on Maize and Soil pH in Semiarid Region

Nitrogen and sulfur play an important role in maize production. The aim of this study was to evaluate the effect of nitrogen (N) and sulfur (S) levels applied in various ratios on maize hybrid Babar yield at Peshawar in 2011 and 2013. Four N levels (120, 160, 200 and 240 kg N ha^?1) and four S levels (20, 25, 30 and 35 kg S ha^?1) were applied in three splits: a, at sowing; b, V8 stage; c, VT stage in ratios of 10:50:40, 20:50:30 and 30:50:20. Grains ear^?1, thousand grain weight, grain yield ha^?1 and soil pH were significantly affected by years (Y), N, S and their ratios, while no effect of N, S and their ratios was noted on ears plant^?1. Maximum grains ear^?1 (390), thousand grain weight (230.1 g) and grain yield (4119 kg ha^?1) were recorded in 2013. N increased grains ear^?1 (438), thousand grain weight (252 g) and grain yield (5001 kg ha^?1) up to 200 kg N ha^?1. Each increment of S increased grains ear^?1 and other parameters up to 35 kg S ha^?1, producing maximum grains ear^?1 (430), thousand grain weight (245 g) and grain yield (4752 kg ha^?1), while soil pH decreased from 8.06 to 7.95 with the application of 35 kg S ha^?1. In the case of N and S ratios, more grains ear^?1 (432), heavier thousand grains (246.7 g) and higher grain yield (4806 kg ha^?1) were observed at 30:50:20 where 30% of N and S were applied at sowing, 50% at V8 and 20% at VT stage. It is concluded that 200 kg N ha^?1 and 35 kg S ha^?1 applied in the ratio of 30% at sowing, 50% at V8 and 20% at VT stage is recommended for obtaining a higher yield of maize hybrid Babar.     

Response of Cherry Rootstocks to Boron and Salinity

ABSTRACT

The objective of the present research was to study the effects of boron (B) and potassium chloride (KCl) induced salinity on growth, nutritional status, and chlorophyll content of the cherry rootstocks CAB 6P (Prunus cerasus L.) and Gisela 5 (Prunus cerasus L. × Prunus canescens L.). Plants produced the longest shoots, more leaves, and the greatest fresh weights of shoots and leaves when treated with 0.025 mM B combined with the lower level of salinity (0.75 dS m^?1). CAB 6P plants retained most of their leaves until the end of the experiment, whereas Gisela 5 plants showed higher leaf shedding. Irrigation of plants with solutions containing 0.2 mM B and electrical conductivities (EC) of 4 dS m^?1 resulted in lower leaf chlorophyll contents (SPAD units) when compared with all other treatments. Nitrogen (N) concentrations of leaves from both rootstocks decreased as the EC of the nutrient solution increased from 0.75 to 4 mM. Potassium (K) concentrations of leaves from both rootstocks increased as salinity levels increased.     

Nitrous oxide flux from komatsuna (Brassica rapa) vegetated soil: a comparison between biogas digested liquid and chemical fertilizer

Biogas production generates digested slurry as a by-product. It can be used as fertilizer especially after its conversion into digested liquid. A microcosm-based study was conducted in order to compare the effects of single application of digested liquid or chemical fertilizer on N₂O flux and crop yield of komatsuna vegetable. Analysis revealed that digested liquid-treated soils released almost equal cumulative N₂O (0.43 g?N m^?2) compared to chemical fertilizer (0.39 g?N m^?2). The uncropped soils treated with the digested liquid and chemical fertilizer released more N₂O compared to corresponding cropped soils. The N₂O emission factor and soil mineral N contents were similar for the digested liquid and chemical fertilizer-treated soils. Plant biomass in the first crop after digested liquid application was significantly higher (5.59 g plant^?1) than that after applied chemical fertilizer (4.78 g plant^?1); but there was no significant difference for the second crop. Nitrogen agronomic efficiency was improved by the digested liquid compared to chemical fertilizer. This study indicates that cumulative N₂O flux was similar after application of the digested liquid and chemical fertilizer, while the overall yield from both croppings was increased in the digested liquid-treated soil compared to chemical fertilizer-treated soil.     

Interaction effect of nitrogen,phosphorus, and zinc fertilization on growth,yield, and nutrient contents of aromatic rice varieties

Abstract

Studies on nutrient interactions in aromatic rice are needed for proper understanding of impact of imbalanced use of nutrients in the era of multi and micro-nutrient deficiencies. A pot experiment was conducted during the rainy/wet season (June–October) of 2013 at New Delhi, to study the interaction effects of two levels each of nitrogen (N) (0 and 120?kg?ha^?1), phosphorus (P; 0 and 25.8?kg?ha^?1), and zinc (Zn; 0 and 5?kg?ha^?1) in two aromatic rice (Oryza sativa L.) varieties, viz. Pusa Rice Hybrid 10 and Pusa Basmati 1121. Application of N, P, and Zn resulted in increase of dry matter (0.91, 0.32, and 0.24?g plant^?1, respectively) 60?days after sowing (DAS) and grain yield of rice (3.68, 1.67, and 1.17?g plant^?1). The increase in yield of rice owing to N application was relatively higher by 0.98, 0.22, and 1.05?g plant^?1, respectively, when either P or Zn or both were applied with N than alone application of N, indicating synergetic effect of P and Zn application with N. The higher concentration and uptake of K in grain (0.25% vs 0.10%) and straw (1.32% vs 0.94%) were observed in the treatment received N than no N, though K was applied uniformly in all the treatments. It indicates positive interaction of N and K. The higher uptake of P in grain and straw was observed when P was applied with N and Zn (3.34 and 2.15?mg plant^?1), or with N (3.26 and 2.11?mg plant^?1) signifying positive effect of N on P uptake in rice.     

Impact of in-season split application of nitrogen on intra-panicle grain dynamics,grain quality,and vegetative indices that govern nitrogen use efficiency in sorghum

Background

The correct rate and timing of nitrogen (N) has the potential to improve sorghum productivity through modified grain yield components and quality. The impacts of in-season split application of N have little documentation.

Aim

An experiment was conducted to determine the optimum rate and timing of N to relate vegetative indices that govern nitrogen use efficiency and to maximize grain yield and quality under different soil types.

Methods

Pioneer 86P20 was grown in three environments on two different soil types following a completely randomized block design with nine N application treatments. Treatments included differing N rates applied at critical developmental stages of sorghum (planting, panicle initiation, and booting), accompanied with high temporal aerial phenotyping.

Results

Opportunities to increase grain protein content while using split N applications were observed, with panicle initiation identified as a critical developmental stage. In-season split application of N enhances grain yield under low soil mineral N. Split application of 31 kg N ha⁻¹ each at the time of planting, panicle initiation, and booting emerged as optimum N treatment to increase protein content in sorghum. Vegetative indices, that is, normalized difference vegetation index and normalized difference red edge index are capable of predicting grain yield and protein content, respectively. Intra-panicle grain numbers and weights were altered significantly at different portions within panicles, with an opportunity to enhance yield potential at the bottom portion. The strong stay-green trait in this hybrid locked a large proportion of nitrogen in the leaves, which warrants the need for balancing stay-green and senescence in sorghum improvement programs.

Conclusions

Findings highlight that in grain sorghum remobilization of residual leaf N into grain is a target to increase yield and grain quality. An optimized stay-green trait balanced with senescence is recommended for enhancing sorghum yield potential.     

Growth and Nitrogen Uptake in Sorghum Plants Manured with Leucaena leucocephala Leaves as Affected by Nitrogen Rate and Time of Application

A pot experiment was conducted to determine the effect of four rates of nitrogen (N) in the form of leucaena leaves and the time of application on the performance of sorghum plants using the ¹⁵N isotopic dilution technique. Results showed that leucaena green manure (LGM) increased dry matter and N yield of sorghum. Nitrogen recoveries of LGM ranged between 23 and 47%. An additional beneficial effect of LGM was attributed to the enhancement of soil N uptake. The best timing of LGM incorporation for obtaining more N derived from LGM, less soil N uptake, and greater dry matter and N in sorghum leaves seemed to be at planting. However, the appropriate timing and rate of LGM to obtain greater dry matter and N yield in panicles, as well as in the whole plant of sorghum, appeared to be at 30 days before planting, particularly a rate of 120 kg N ha^?1.     

Cumulative Effect of Soil and Foliar Application of Nitrogen,Phosphorus, and Sulfur on Growth,Physico-Biochemical Parameters,Yield Attributes,and Fatty Acid Composition in Oil of Erucic Acid-Free Rapeseed-Mustard Genotypes

ABSTRACT

The feasibility of split (soil + foliar) applications of nitrogen (N) and phosphorus (P) and addition of a small quantity of sulfur (S) in the spray was tested for improving performance of rapeseed-mustard genotypes in a factorial randomized field experiment. Three genotypes (two erucic acid free, viz. Brassica napus L. cv. ‘Hyola PAC – 401’ and Brassica juncea L. Czern. and Coss. cv. ‘TERI (0E) M 21-Swarna’, and one best performing high yielding Brassica juncea L. cv. ‘Rohini’ as a check) were grown with four soil (B) plus foliar (F) applications of N, P, and S with uniform basal 30 kg potassium (K) ha^{? 1} (K₃₀), viz. (i) the optimum soil-applied treatment supplemented with the spray of deionized water (B_N90P30 + Fw) comprising control, (ii) B_N70P30 + F _N20, (iii) B_N70P28 + F_N20P2, and (iv) B_N70P28 + F_N20P2S2. Soil Plus foliar application of nutrients, particularly B_N70P28 + F_N20P2S2, improved their performance with respect to growth characteristics (shoot length plant^{? 1}, leaf number plant^{? 1}, area leaf^{? 1}, leaf area index, fresh weight plant^{? 1}, and dry weight plant^{? 1}), physico-biochemical parameters (net photosynthetic rate, stomatal conductance, carboxylation efficiency, water use efficiency, carbonic anhydrase activity, leaf NPK content, and N use efficiency), yield attributes (pod number plant^{? 1}, seed number pod^{? 1}, 1000-seed weight, seed yield ha^{? 1}, oil content, and oil yield ha^{? 1}), and fatty acid composition in oil of these genotypes. The cultivar ‘Hyola PAC-401’ performed best particularly with B_N70P28 + F_N20P2S2. The improvement in the response of genotypes to the split application of nutrients may be attributed to their ready availability through foliar application.